• Abstract
  • Anti-aliased fonts can damage eyesight - writeup

JTL Thanks!!

On Mac and Chromebook it says Default, so it inherent from the OS
On Mac default for the OS is Enabled
On Chromebook have no clue how to check, haven't enabled developer mode yet, but visually I can tell it's Disabled.

Just for any case this OS setting not to change, I have manually disabled it in chrome
chrome://flags/#lcd-text-aa

Can't speak about Win, haven't used for too long. My original issue started 2011/2012, I was on Win 7 back then, I had switched from XP, I can't tell now for how long it was after the switch but I think I used it for at least a month. So I guess or I built this intolerance gradually or I got auto update with "Clear Type" fonts! But it all started on what seemed a regular morning, went to the office, turned on the monitor and I couldn't look at the screen! I had x8 Dell CCFLs, couldn't look at any of them. When went home, I couldn't look at my MBP 2010 too! I can't recall but I think I did not have problems then with my 2G iPhone...

This is very interesting. I will test it. Do you think in windows 10 of the newer versions this could work too? I remember playing around with cleartype but having no success, maybe it would work if its completely overridden.
Btw. IRIS software had this option of overriding all system fonts into non-aliased version, have you tried it? Could be a good solution to get rid of this for certain so then testing it is easier.

    martin With regards to Windows 10 I don't know.

    MS has been moving away from cleartype for a long time now even in 7. If you installed a current version of IE, you lost cleartype. If you installed a version of Office higher than 2010, you lost cleartype.

    It only works in landscape orientation, and pretty much only on white backgrounds.

    Fonts were specifically designed to be used with "cleartype" rgb subpixel anti-aliasing (e.g. Calibri, etc.), or no anti-aliasing (Verdana, Georgia, etc.), or greyscale anti-aliasing.

    Match the fonts to the rendering you prefer, you'll get better display results.

    It's true about the Verdana/Georgia and a few others. They were done as bitmaps first, and then outlines wrapped around them which is never done anymore. I love Verdana on the screen.

    martin Will give it a try to Iris tomorrow, haven't used it yet.

    I think you understood me the reverse way. I cannot handle smooth fonts and shapes and since ~2012 everything I have put my eyes on seems uses this by default!
    Keywords for this are font rasterization, subpixel rendering, font anti aliasing, subpixel AA, LCD font smoothing (Apple), ClearType (Windows)

    As soon I turned this off, I could instantly feel more comfort. I would say 90% my issue is solved, but there is still something left.

    I have no problems at all with my new discovery Chromebook, I can sit now 12-14h a day without problems (this is super shitty quality and flickers like crazy but I don't have issues with flicker).

    Disabled the smoothing on my Air and Retina too. The Air is much more comfortable now, the Retina is slightly improved but still not good enough :S

    I also have enabled "Reduce Transparency". This feature on the iPhone X gave me similar improvement to the Retina after disabling smoothing.

    I noticed that I should not enable "Increase Contrast" as that worsens my situation.

    I matched the fonts on my Retina chrome with what's on the Chromebook
    https://www.fontsquirrel.com/fonts/tinos
    Standard font: Tinos
    Serif: Tinos
    Sans-serif: Arimo
    Fixed-width: Cousine

    I plug them into x2 same monitors "Lenovo ThinkVision P27h-10 27" and match the resolution 1600x900 (60HZ) but I still can't get the comfort level from the Retina match that of the Chromebook. That external monitor where the Mac Retina is attached still produces much smoother picture (although now can visibly tell anti aliasing is off). I think it has something to do with the color depth/bit depth/buffer frame. Installed SwitchResX and Display Maestro 2 but both of them show only Millions. The Chromebook is maybe in thousands, not sure how to check :S Or maybe its 8 vs 16 vs 24 vs 32 bit

    • JTL replied to this.

      JTL
      This naming is confusing indeed: 8 bits per channel may equal 24 bits per 3 RGB channels, as well as 32 bits per RGB + transparency. I initially thought that 24 and 32 bit screens are different
      E: I've just checked the link you provided - it says the same thing 😃

      • JTL likes this.

      24 vs. 32 bit screens is ALSO misleading - most screens are in fact 18-bit and simulate 24-bit. There are a VERY FEW 30-bit screens.

      • JTL replied to this.

        Gurm 30-bit = 10-bit in marketing speak iirc.

        • Gurm replied to this.

          JTL Correct. Which, as I said, there are like 5 of. It's frustrating, but most displays are 6/24 bit. This is why every device flickers. 😉

          oh looks it's not the bit depth that is my second problem but DPI!! Accidentally noticed that under SwitchResX there are HiDPI and same resolution as regular ones, as soon I picked non HiDPI my Mac discomfort lowered (both on the Retina display and the External one).

          Besides not being able to tolerate "smooth fonts" looks I can't tolerate DPI > 1x
          https://wiki.archlinux.org/index.php/HiDPI#Chromium_.2F_Google_Chrome

          Here is output of chrome://gpu/ output from my comfortable chromebook
          Display(s) Information
          Info Display[12528934998507520] bounds=[0,0 1241x698], workarea=[0,0 1241x650], scale=1.1, internal.
          Color space information {primaries:INVALID, transfer:INVALID, matrix:INVALID, range:INVALID}
          Bits per color component 8
          Bits per pixel 24
          Info Display[13702326689085187] bounds=[1241,0 1600x900], workarea=[1241,0 1600x852], scale=1, external.
          Color space information {primaries_d50_referred: [[0.6663, 0.3285], [0.3202, 0.6144], [0.1480, 0.0513]], transfer:0.0000x + 0.0000 if x < 0.0000 else (1.0000x + 0.0000)**2.2000 + 0.0000, matrix:RGB, range:FULL}
          Bits per color component 8
          Bits per pixel 24

          At this point I use same external monitors, same font, no smoothing, DPI scale 1 and the Mac still gives me slight discomfort, it's has slight blurness, however I would say 95+% my situation has been improved 😃

          Looks if iPhone X feels worse than iPhone 8 then it's the DPI, DOES SIZE MATTER? section on this link
          https://www.zdnet.com/article/iphone-x-or-iphone-8-price-size-camera-all-factor-in-your-buying-decision/
          as it has higher scale.

          • hpst replied to this.

            Im thinking about this and it makes quite a lot of sense. Imagine when some mentioned that older OS on a good comfortable phone was ok and new one wasnt. Maybe the font rendering in that new update changed, the fonts are more blurry and impossible to fix your vision onto, thus the issues.
            Or of course dithering which is still hard to prove and Im not sure why it would change inbetween software updates, but it could of course.
            If every outline of every box, font and image is anti-aliased (blurry), then it would makes sense how we feel "unable to focus" most of the time. Its very simple, easily overlooked and for example on iphones impossible to fix. Supposedly though you can change fonts on jailbroken iphone, would be a good idea to try that.
            Technically also if you have the same OS on an older and newer iphone, the OS still knows which iteration of iphone it is and could therefore still render differently between those two devices.

            daniel_mate

            Is DPI the same as scaling in this context? On KDE neon there is a scaling option and since my panel is 1080 its way too small at 1.0 and I use 1.5 to make things big enough, but I cannot use that laptop due to strain anyway. I also tried leaving scaling at 1.0 and reducing display resolution to 1600x900 but it didn't change the strain. It would be great if simply a set of rendering/scaling/resolution settings could solve this.

              hpst yes I think I use it in same context
              When picked same resolution on the Retina, just non HiDPI, the scale changed from 2 to 1 and now both my retina and Air laptops feel same...tho still have discomfort but at least my eyes don't feel like they want to flip instantly (after disabling anti-aliasing too).

              • hpst replied to this.

                daniel_mate Do you know Linux? I am trying to figure out how to replicate your results in Linux. If I put scaling to 1 or don't increase DPI in another place the text is too tiny on a 1080 14" screen. There just isn't any way to get a 1080 14" display readable without adjusting SOMETHING to make text and elements larger.

                  hpst I do.

                  I got Red Hat Enterprise wks last week to experiment at work
                  It has NVIDIA Corporation GK107GL [Quadro K420] (rev a1) + Lenovo ThinkVision P27h-10 27 monitor.
                  It had pre-installed the nvidia settings tool
                  As is it came with grayscale auto aliasing.
                  Disabled dithering over it too, but have no clue if it did anything.
                  I use 1600x900, and chrome says scale=1...yeah this resolution is pretty big (huge everything)
                  This setup feels same to me with the Macs (after disabling their default sub-pixel antialiasing on them)

                  This Linux and the Macs give some blur/smooth feel of everything (not just the fonts), where the good Chromebook and Matte TN Mac feel sharp and pixelized (also talking about pictures not just fonts)

                  ...on my to do is to experiment with different live linux CDs on the Macs.

                  2 months later

                  daniel_mate

                  In MacOS Mojave, unless I enable old-style font smoothing, I get a lot of eye strain and migraines. Even if I pick "strong" font smoothing instead, it's just too weak and the text is too faint and spiderey.

                    Ananiujitha I think that is normal. This Mojave "issue" got so many write ups cause almost everybody on non-retina displays is affected. The change is visible for worse quality and I guess even people with good eyes get strain with it after short time. ...but for people with bad eye/s like me that can look for few minutes only the bad quality one is more tolerable than the beautiful smooth one.

                    • AGI likes this.
                    a year later

                    Been having the same exact issue on Linux for years. Different GPUs, displays (except for IPS), drivers, playing with fonts and whatnot never solved it for me. Yes, it's an issue which you can only feel, not see. Yes, you can't focus on text or elements for too long, everything feels fuzzy, juddery and makes your eyes wanna roll inside your sockets. This stupid thing has been keeping me off Linux and I don't get it why only a few people are affected by this. It doesn't make any sense. What exactly is missing here, and what is so special about Windows? Whom do we have to address about this? Nvidia, ATI, Xorg or Kernel devs? WHAT do we tell them exactly? These are all 1 million dollar questions. We have a discussion open here as well: https://ledstrain.org/d/785-eyestrain-when-switching-from-windows-to-linux/31

                    Please, join if you have any solutions or just want to help us expand our "strained" community.

                    a year later

                    I think using a bad monitor is the primary reason for damaged eyesight. Pick a better monitor from here

                    dev